CATALYTIC UPGRADING OF USED LUBRICATING OILS

ABSTRACT

Several commercial catalysts were tested for their activity for upgrading waste lubricating oils. The feedstock was vacuum distilled to remove the light and the heavy ends. Two trickle-bed reactors placed in series were employed, the top reactor contained a high surface area alumina and the bottom reactor the catalyst. A Ni-Mo-AI₂O₃ catalyst was selected for further study on the basis of its higner activity and activity maintenance. Several different hydrogen pressures, reactor temperatures, and liquid volume hourly space velocities were employed to arrive at the most optimum process conditions. This paper will discuss the effect of catalyst and process conditions on the product liquid color, viscosity, nitrogen, and sulfur content.     

Aromatization of FCC Gasoline Over Modified HZSM-5 Catalyst

Zinc and phosphorus incorporated HZSM-5 catalyst was prepared by adopting incipient wet co-impregnation (Zn-P/HZSM-5). Zn-P/HZSM-5 catalyst exhibited the lowest acidity but the highest aromatization activity with stable performance in the studied period of 16 hr. The process conditions on aromatization reaction and the coke deactivation mechanism of Zn-P/HZSM-5 catalyst were studied on a small-scale, fixed bed reactor using FCC naphtha (75-120°C). The weight contents of ZnO and P₂O₅ were 2% and 4%, respectively. Results showed that Zn-P/HZSM-5 catalyst under a temperature of 450°C, liquid hourly space velocity of 1.0 h^-1, and pressure of 0.1 MPa, the conversions of olefins and alkanes are 96.77% and 88.94%, respectively, the contents of olefins, aromatics in liquid product are 6.79% and 74.57%, respectively. Carbon deposition was the major reason for catalyst deactivation due to the catalyst's good performance as a fresh catalyst after regeneration. All of the blending products fitted the standards of Chinese gasoline.     

Performance Evaluation of Certain Commercial Hydrotreating Catalysts in a Pilot Plant Reactor

The performance of different hydrotreating catalysts was evaluated in a pilot plant trickle bed reactor using a feedstock collected from an industrial diesel hydrodesulfurization unit. The feed is a typical blend of straight run diesel fractions from crude distillation units, FCC cycle oils, heavy naphtha, etc. It contains 1.11 wt% of sulfur, 0.12 wt% of nitrogen, and 34.6 wt% of total aromatics. The catalyst samples evaluated in the present work are commercially available high activity new generation catalysts being used in many refineries for diesel hydrodesulfurization application. The experiments were carried out at a constant pressure of 40 kg/cm² and a constant H₂/oil ratio of 200 l/l. Experiments were performed to study the influence of reactor temperature and liquid hourly space velocity on product quality. The reactor temperature was varied from 320-360°C at different liquid hourly space velocities. The liquid hourly space velocity was varied from 1.0 to 2.5 h^-1 at different reactor temperatures. The feed and product samples hydrotreated in the pilot plant reactor were analyzed to determine their physical properties and measure sulfur, nitrogen, olefinic, poly-, di-, monoaromatic, and naphthenic hydrocarbons. Catalyst C was found to have the highest hydrodesulfurization activity among the catalysts studied. The hydrodesulfurization activity of catalyst A and catalyst B are similar. Catalyst D was found to have lower hydrodesulfurization and higher hydrodenitrogenation activity compared to catalyst C.     

基于响应曲面法的环管装置聚丙烯相对分子质量的模拟及优化

基于响应曲面法（RSM）,采用5因素3水平的Box-Behnken设计,通过Aspen Polymers Plus软件模拟了环管式丙烯聚合过程,探讨了聚合温度、压力、丙烯质量流量、催化剂用量、H₂体积分数对环管反应器出口聚丙烯(PP)相对分子质量的影响,建立了以环管反应器出口PP相对分子质量为响应函数的数学模型,对聚合反应条件进行了优化,确定了满足PP相对分子质量为(1.22±0.004)×10.5的最佳操作条件。结果表明,在聚合温度71.1℃、压力3.25 MPa、丙烯质量流量671×10.3 kg/h、催化剂用量0.20 kg/h、H₂体积分数3.12%的最佳操作条件下,得到的PP相对分子质量为1.22075×10.5,与目标值的偏差仅为0.061%;采用响应面法优化环管装置生产具有目标相对分子质量PP的操作条件可行,建立的数学模型能够较准确地预测PP相对分子质量,可以用于指导工业生产。     

IN-SITU ACTIVATION OF METHANOL SYNTHESIS CATALYST IN A THREE-PHASE SLURRY REACTOR

In the liquid phase methanol synthesis process, syngas reacts in the presence.of fine catalyst particles slurried in the oil phase, in a three phase slurry reactor system. A method for activating high concentration ( ≤25 wt. %) of the CuO-ZnO-Al₂O₃ catalyst in the catalyst-oil slurry has been successfully developed. This catalyst activation process can be of crucial significance in the research and development of the methanol synthesis process in a liquid entrained reactor.

The reducing gas contains 2% hydrogen in nitrogen mixture and this activation procedure is carried out at a pressure of 125 psi. The catalyst-oil slurry is subjected to a controlled temperature ramping from 110° to 250° C. The catalyst has beemshown to be effectively reduced after following this activation procedure, that is valid especially for high catalyst loadings in slurry. Since the reduction is carried out in the process liquid medium and inside the reactor system, the catalyst-oil slurry after the treatment is ready for the synthesis of methanol.     

三乙胺基SO3H-功能化离子液体催化合成己二酸二丁酯

以三乙胺为主要原料合成了5种BrØnsted酸性离子液体,考察了不同结构离子液体对合成己二酸二丁酯的催化活性,并将离子液体酸性强弱与酸催化活性进行关联,同时优化反应温度、原料配比、反应时间、催化剂用量等反应条件。结果表明,以N (4 磺酸基)丁基三乙胺硫酸氢盐离子液体为催化剂,添加带水剂环己烷,在反应温度110℃、n(1 Butanol)/n(Adipic acid)=6、m(Catalyst)/m(Adipic acid)=001、m(Cyclohexane)/m(Raw materials)=015、反应时间3 h的条件下,己二酸转化率达到99%;经连续重复使用7次,该催化剂仍可保持很高的催化活性。     

Etherification Performance of Transition Metals Modified β-Zeolite Catalyst

The etherification experiment for FCC light gasoline on transition metals modified Hβ zeolite was studied in a fixed-bed reactor. The effect of preparation condition of catalyst on the catalyst's activity, stability, and the effect of reaction temperature, methanol/tert-olefin molar ratio, and liquid hour space velocity on the etherification reaction were discussed. The experimental results showed that the different metals modified Hβ zeolite had different etherification performances. And the conversion of tertiary carbon-olefins of the molybdenum modified Hβ zeolite, which was loaded 3%, was higher 6.0% than the Hβ zeolite. The optimal reaction conditions were temperature 70-80°C, liquid hour space velocity 1.0 h^-1 and methanol/tert-olefin molar ratio 1.05. The modified Hβ zeolite catalysts possessed favorable prospect for its higher stability.     

HYDROPROCESSING OF COAL-DERIVED MIDDLE DISTILLATE

Coal-derived middle distillate, boiling range 437 to 623^°K, was hydrotreated in a fixed bed reactor with a commercial N_iO-M_o0₃/ Al₂O₃ catalyst. The feedstock contained predominantly highly-substituted aromatics. The product heteroatom content and aromaticity decreased with increased process temperature or pressure. Aromaticity was proportional to liquid space velocity. Heteroatonms could be effectively reduced at hydroprocessing conditions of 653^°K, 10 MPa, and 2 WHSV. Experimentally-derived cetane number was found to be proportional to product aromaticity. Severe hydroprocessing conditions were required to produce diesel fuel of acceptable cetane number.     

钾基复合催化剂对高硫石油焦气化性能的影响

以高硫石油焦为研究对象,探讨了水蒸气气氛下不同钾基催化剂、铁基催化剂以及K-Fe、K-Ca复合催化剂对高硫石油焦气化性能的影响。在1023 K、0.1 MPa下,钾基催化剂中KOH催化活性最高,而铁基催化剂中FeSO₄催化活性最高;在KOH基础上添加铁基催化剂后其催化性能有所降低;在K-Ca复合催化剂中,5%KOH和3%CaO(质量分数)复配时,催化剂的催化性能最好,石油焦碳转化率达到最高值61.33%,继续增加CaO添加量,K-Ca复合催化剂的催化性能降低。采用BET和XRD对K-Ca复合催化剂的催化作用机理进行研究,发现CaO的造孔作用以及石油焦气化反应过程中生成的双金属碳酸盐K₂Ca(CO₃)₂共同促进了气化反应的进行。而在压力增大的条件下,由于K-Ca复合催化剂中双金属碳酸盐K₂Ca(CO₃)₂的晶型发生转变,导致其催化活性相比添加KOH催化剂时降低。     

THE ROLE OF WATER IN METHANOL SYNTHESIS

This work focuses on the influence of water in determining the rate of methanol synthesis over CuO/ZnO/Al₂O₃ catalysts. The experimental investigations were conducted in a 1-L slurry reactor based on the novel liquid phase methanol synthesis process. The liquid medium used was a blend of paraffinic and naphthenic mineral oils with a mean molecular mass of 250. It was found that the methanol rates attained a maximum at an optimal water content which was dependent on the reaction temperature. The catalytic activity was found to decline with time at lower temperatures in the presence of a relatively large excess of water. The influence of water was also found to be firmly linked to the corresponding carbon dioxide content in the reactor feed. The experimental data bear additional significance because this was the first such study to be performed on the liquid phase process. Emphasis was therefore placed on the use of a CO-rich syngas in order to simulate anticipated process conditions.     

FCC Gasoline Hydroisomerization Over Pt/HZSM-5 Catalysts

Pt/HZSM-5 bifunctional catalyst of fluid catalytic cracking (FCC) gasoline hydroisomerization was prepared. The influence of calcinations and reduction conditions, the metal-incorporation technique, and metal loading on the hydroisomerization of FCC gasoline over the Pt/HZSM-5 bifunctional catalyst was studied. The process opinion catalyst of FCC gasoline hydroisomerization was obtained under the condition of temperature 290-300°C; pressure 1.5-2.5 Mpa; liquid hour space velocity (LHSV) 2.0-3.0 hr^-1; V(H₂)/V(Oil) = 2.0-3.0. The results showed that calcination conditions have a significant influence on ion-exchanged catalysts, as they control the final metal distribution. The reduction conditions and the method used for platinum incorporation were found to be important factors that affected both the activity and selectivity of the catalysts. Pt/HZSM-5 bifunctional catalyst possessed good activity for hydrogenation and isomerization. The olefin hydrocarbons of FCC gasoline were hydrogenated and the stability of FCC gasoline was improved under condition of unchanged octane number.     

KINETIC RATE EXPRESSION FOR METHANOL SYNTHESIS IN A LIQUID ENTRAINED REACTOR

In the three phase entrained reactor for the liquid phase synthesis of methanol, the catalyst-inert oil slurry is pumped through the tubular reactor and syngas is fed to the reactor cocurrently with the upward flow of slurry.

According to an elaborate experimental design plan, the effect of different operating conditions on the liquid phase synthesis of methanol in an entrained reactor, was studied. The parameters of this experimental study included reactor temperature, reactor pressure, slurry flow rate, syngas flow rate, slurry holdup tank pressure, and syngas composition.

The data obtained from the experiments at low catalyst loading in slurry, were used to develop a kinetic rate expression for the liquid phase methanol synthesis process in an entrained reactor. This in turn helps the scale-up and commercialization of the methanol synthesis process in an entrained reactor.     

苯酐生产技术进展

介绍了通过邻二甲苯工艺路线生产苯酐的几种技术,包括传统的单固定床氧化反应器、开发的双固定床反应器、用马来酸酐作为液体低共熔混合物回收苯酐和基于改善的耐磨催化剂的流化床反应器。探讨了生产技术的经济性,并对催化剂技术、工艺研究与开发及其工业现状进行了综述。     

磁稳定床反应器中己内酰胺加氢精制应用研究

采用工业原料在6 kt/a中试装置上对以镍系非晶态合金为催化剂的磁稳定床反应器中己内酰胺的加氢精制过程进行了研究,考察了各种操作参数对反应结果的影响以及催化剂的稳定性。试验结果表明,己内酰胺水溶液经预溶氢后磁稳定床反应器加氢精制或气液固三相磁稳定床反应器加氢精制,在氢液体积比0.7-1.5、反应温度80-100℃、反应压力0.4-0.9 MPa、空速30-50 h-1、磁场强度15-32 kA/m的条件下,加氢后溶液的高锰酸钾值(PM)从50 s提高到2 000 s以上,催化剂寿命达3 200 h以上;与工业上搅拌釜式己内酰胺加氢精制工艺相比,催化剂耗量可降低60％。     

滴流床反应器操作参数对异戊二烯选择加氢反应的影响

采用自制的LNEH-1催化剂,以含异戊二烯的环己烷为原料,在滴流床中考察了操作条件对异戊二烯选择加氢反应的影响。考察了滴流床反应器中催化剂装填位置、液速、气速、气液比和压力等因素对异戊二烯选择加氢反应的影响。实验结果表明,催化剂装填在液相区有利于提高异戊二烯转化率,但单烯收率降低;气速对异戊二烯选择加氢和深度加氢的影响明显大于液速;液速由0.07m/min增加到0.29m/min时,异戊二烯转化率和单烯收率基本不变;气速由0.11m/min升至0.27m/min时,异戊二烯转化率由96.6%增至98.5%,单烯收率从8.90%降至4.14%;气体与液体的体积比和液态空速一定时,液速和气速同时增加不利于异戊二烯选择加氢反应;氢气分压对异戊二烯选择加氢反应的影响比系统压力的影响更大。     

费-托合成催化剂CNFT-1的工业试验

费-托合成催化剂CNFT-1的工业试验在4 Mt/a煤制油装置的两个系列费-托合成反应器中分两个阶段进行,第一阶段为逐步替换原有催化剂的工业试验,最终置换率超过了95％,结果表明:催化剂CNFT-1性能满足工业生产要求.第二阶段基于工业替换试验数据,采用浆态床费-托合成反应器模拟软件,对采用100％催化剂CNFT-1运...     

滴流床反应器中流体流动规律及其对异戊二烯加氢反应的影响

在滴流床冷模实验中,考察了气含率与压降随气液条件的变化规律,并在热模条件下以含异戊二烯的环己烷为原料进行选择性加氢反应,考察了催化剂装填位置、液速和气速对异戊二烯选择加氢反应的影响。结果表明,相同液速条件下,气速小于0.88 m/min、气液体积比小于4.0时,气含率随着气速的加大而急速增加,压降降低,随后气含率增加趋势变缓,压降增大。位于液相为主区域的催化剂其异戊二烯加氢活性和异戊烷选择性明显高于气相为主的催化剂,异戊二烯加氢反应在整个滴流床反应器中是不均匀的。气速对异戊二烯选择加氢和深度加氢的影响明显大于液速。液速由0.07 m/min增加到0.29 m/min时,异戊二烯转化率和异戊烷选择性不变;但气速由0.11 m/min升至0.27 m/min时,异戊二烯转化率和异戊烷选择性分别由96.6%和91.0%增加到98.5%和96.1%。     

METHANOL PRODUCTIVITY COMPARISON BETWEEN AN AGITATED SLURRY REACTOR AND AN ENTRAINED REACTOR

The effect of various operating conditions including the catalyst loading in slurry, on the productivity of methanol in an agitated slurry reactor were studied. The modeling of the mechanically agitated slurry reactor was performed with the aid of the reaction rate expression and the gas-liquid mass transfer correlation that were developed, to predict the rate of methanol production for any inlet condition

The equilibrium limitation encountered in the liquid phase methanol synthesis process in an agitated slurry reactor can be alleviated by conducting this process in an entrained reactor, where the product methanol formed is continuously flashed out of the system. After developing a kinetic rate expression and a gas-liquid mass transfer correlation, the modeling of the entrained reactor was performed to predict the reactor productivity for any process condition. The rate of methanol production predicted for nominally identical operating conditions in an entrained reactor and in a mechanically agitated slurry reactor are compared with the aid of the computer models developed     

MASS TRANSFER IN THE LIQUID PHASE METHANOL SYNTHESIS PROCESS

The mass transfer characteristics of the liquid phase methanol synthesis process were experimentally investigated using a one-liter, mechanically agitated slurry reactor. The CuO/ZnO/Al₂O₃ catalyst was crushed to -140 mesh and suspended in an inert mineral oil (Witco # 40). The catalyst loading was varied within limits of experimental feasibility. The effects of temperature, pressure, level of oil, impeller speed, and gas flow rate on the overall gas-liquid mass transfer coefficient K_Lia_B were studied

The results obtained using a two-level, half-fractional factorial design of experiments indicated that the impeller speed, feed flow rate, and temperature had significant effects on the mass transfer coefficient at the experimental conditions examined. Correlations were developed for the Sherwood number based on the Reynolds number, the Schmidt number, the reciprocal gas flow number, the gas-liquid viscosity ratio, and the dimensionless temperature. A simplified power-law type approach was also used to correlate the overall gas-liquid mass transfer coefficient with the impeller speed, gas flow rate, and dimensionless temperature.     

APPLICATION OF A THREE PHASE HETEROGENEOUS MODEL TO ANALYSE THE PERFORMANCE OF A PILOT PLANT TRICKLE BED REACTOR

A three phase heterogeneous model was used to analyse the performance of a pilot plant trickle bed reactor employed for hydrodesulphurisation of atmospheric gas oil fraction. [6] have presented a three phase heterogeneous model for hydrodesulphurisation of vacuum gas oil in a trickle bed reactor and showed that it can be used to include the inhibiting effect of hydrogen sulphide on sulphur conversion. This model was based on two film theory and incorporated mass transfer phenomena at the gas-liquid and liquid-solid interface. The chemical reaction rates were described using Langmuir-Hinshelwood mechanism. Though heterogeneous models are assumed to be more rigorous than the pseudo homogeneous models, the validation data using different reactors and reaction systems is scarce. The present study aims to validate the model with particular attention to show the influence of hydrodynamic parameters and intrinsic rates of reaction on reactor performance. The model predictions were compared with experimental observation under wide range of operating conditions. The data generated on hydrodesulphurisation of an atmospheric gas oil fraction over commercially available CoO-MoO₃/A1₂O₃ catalyst was used to test the model. The simulation showed good agreement with the experiments carried out in a wide range of operating conditions.